KR101172979B1 - Circuit breaker - Google Patents

Abstract

[PROBLEMS] To obtain a circuit breaker that can improve the durability of the switchgear and reduce the cost and space.
[Solution] The lower link 46 for driving the crossbar 30, the lever 44 which meshes with the latch of the removal device 33 and pivots on the bearing part of the frame at the time of tripping; An upper link 45 pivotally supported by the lever 44 and coupled to the lower link 46 through a spring pin 47 to form a toggle link together with the lower link 46; A main spring 48 having a driven side coupled to the 47 and a handle arm 42 pivotably pivotally supported on a frame 43 fixed to the case by being coupled to the driving side of the main spring 48. In the circuit breaker having the opening / closing mechanism 40, the lever 44 is formed of a single metal plate including the lever pivot shaft portion 44a, and an arc-shaped portion having a central angle greater than 180 degrees to the lever pivot shaft portion 44a. 44a2).

Description

Circuit breaker {CIRCUIT BREAKER}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to circuit breakers such as circuit breakers and earth leakage breakers, and more particularly, to durability improvement of switchgear units.

A general circuit breaker employs a well-known contact inserting mechanism using a toggle link, and the rotation shaft of the lever does not penetrate the mechanism portion, which is advantageous for miniaturization since the constraint of the main spring moving space is reduced. In addition, the rotation of the lever needs to be transmitted to the accessory device beyond the upper wall, but the member which transmits the rotation of the lever is preferably configured around the rotational axis of the lever as much as possible to secure insulation between the phases. .

Due to such a restriction, in the conventional circuit breaker, a part of the lever is bent to form a rotating shaft (see Patent Document 1, for example).

[Patent Document 1] Japanese Unexamined Patent Publication No. 2008-140692 (Fig. 8)

As described above, in the conventional circuit breaker, the cross section of the rotational shaft of the lever is approximately square, and the contact with the shaft hole is limited to the angle or the cross section, so that the contact surface pressure becomes large. There was a problem that a misalignment occurs.

It is also possible to form the pivot shaft of the lever by extrusion rather than bending, but there is a limit in the outgoing height, and when a separate part such as a toggle link is interposed between the lever and the frame. It is necessary to cut out three times or more of the plate thickness, and there is a problem that it is difficult to secure the strength of the pivot shaft of the lever.

On the other hand, the case where the rotational shaft comprised from the other component is joined also to the lever can be considered, but it was difficult to simultaneously satisfy the problems such as securing the joining space, dimensional accuracy and strength, and reducing the component cost and assembly cost.

This invention is made | formed in order to solve the above subjects, and obtains the circuit breaker which can improve the durability of a switching mechanism part.

The circuit breaker according to the present invention holds a movable contact having a movable contact at one end or both ends, a fixed contact foldable with the movable contact, and a movable contact and pivotably rotatable. A supported crossbar, a lower link for driving the crossbar, a lever engaged with a latch of the removal device, pivoted by the bearing portion of the frame at the time of tripping, and pivotally supported by the lever; In addition, the upper link is coupled to the lower link through the spring pin, the upper link constituting the toggle link with the lower link, the main spring coupled to the driven side to the spring pin, and coupled to the driving side of the main spring, the circuit breaker A handle arm pivotally pivotally supported on a frame fixed to the case, wherein the lever is formed of a single metal plate including the pivot shaft portion of the lever, and the pivot shaft portion has a center angle of 180 degrees. It has an arc-shaped part formed in a surface having a cross-sectional shape which is a large arc-shaped.

According to the present invention, by providing an arc-shaped portion formed in a surface having an arc-shaped cross section whose central angle is greater than 180 degrees on the pivot shaft of the lever in the opening and closing mechanism portion, the contact with the bearing portion of the frame is brought into surface contact, Since the contact surface pressure can be reduced, the durability of the opening and closing mechanism can be improved.

1 is a perspective view showing a trip state of a circuit breaker in Embodiment 1 of the present invention.
2 is a side sectional view showing a tripping state of a circuit breaker according to the first embodiment of the present invention.
3 is a side sectional view showing an off state of a circuit breaker according to the first embodiment of the present invention.
4 is a side sectional view showing an on state of a circuit breaker according to the first embodiment of the present invention.
Fig. 5 is a perspective view of principal parts showing single open / close mechanism parts, movable contacts, and crossbars in a state of turning off the circuit breaker in Embodiment 1 of the present invention.
6 is a perspective view showing a lever of a circuit breaker according to the first embodiment of the present invention.
Fig. 7 is a side view showing the lever of the circuit breaker according to the first embodiment of the present invention.
It is a side view which shows the lever rotation shaft part of the lever of the circuit breaker in Embodiment 1 of this invention.
Fig. 9 is a perspective view showing the mounting of the lever rotation transmission member to the opening / closing mechanism portion in the on state of the circuit breaker according to the first embodiment of the present invention.
It is explanatory drawing which shows the load on the lever of the circuit breaker in Embodiment 1 of this invention.
Fig. 11 is an enlarged view of an essential part showing the engagement portion between the lever and the latch of the circuit breaker according to the first embodiment of the present invention.
It is a side view which shows the lever rotation shaft part of the lever of the circuit breaker in Embodiment 2 of this invention.

Embodiment 1

1 is a perspective view showing a trip state of a circuit breaker according to a first embodiment of the present invention, FIG. 2 is a side cross-sectional view showing a trip state, FIG. 3 is a side cross-sectional view showing an off state, FIG. 4 is a side cross-sectional view showing an on state, 5 is a perspective view of an essential part showing single open / close mechanism, movable contactor and crossbar, FIG. 6 is a perspective view showing the lever 44, FIG. 7 is a side view showing the same lever 44, and FIG. 8 is a lever pivot shaft part ( Fig. 9 is a perspective view showing the mounting of the lever rotation transmission member 13 to the on / off mechanism in the on state, and Fig. 10 is an explanatory view showing the direction of the load applied to the lever pivot shaft 44a, (a ) Represents an on state, (b) represents an off state, and (c) represents a trip state. 11 is the enlarged view of the principal part which expands and shows the engaging part 44b with the latch 34 in the lever 44. As shown in FIG.

In Fig. 1, the circuit breaker 100 is constructed using a case 10 consisting of a base 11 and a cover 12 formed of an insulating material. On the base 11, circuit break units 20A, 20B, and 20C of three phases are arranged in parallel with each other, and an opening / closing mechanism portion 40 is disposed above the circuit break unit 20B in the center. The base 11 has a pair of outer walls 11A and 11B and a pair of partition walls 11C and 11D. A circuit blocking unit 20A is disposed between the outer wall 11A and the partition wall 11C, and a circuit blocking unit 20B is disposed between the partition walls 11C and 11D, and the partition wall 11D and the outer wall are disposed. A circuit interruption unit 20C is disposed between 11B. The cover 12 covers the circuit blocking units 20A, 20B, and 20C of each phase on the base 11 and the opening / closing mechanism part 40, and the operation handle 41 of the opening / closing mechanism part 40 protrudes from the cover 12. do. In addition, in FIG. 1, the cover 12 cut | disconnects the part which covers circuit interrupting unit 20A, 20B, and shows them inside.

Circuit break units 20A, 20B, and 20C in each phase are configured in the same manner, and specific configurations thereof are shown in FIGS. 2, 3, and 4. 2, 4, and 5 show the center circuit break unit 20B, but other circuit break units 20A and 20C are configured in the same manner. As shown in Figs. 2, 3 and 4, the crossbar 30 is common to the circuit break units 20A, 20B and 20C of each phase, and is orthogonal to the circuit break units 20A, 20B and 20C of each phase. It is disposed on the base 11.

The circuit blocking units 20A, 20B, and 20C in each phase include a power supply terminal 24 provided in the base 11, a fixed contact 21 provided to extend from the power supply terminal 24, and the fixed contact 21. And a movable contact 22 which is in contact with the movable contact 22, a movable contact 22 which is provided at one end and is rotatably held by the crossbar 30, and is connected to the movable contact 23. It is connected to the overcurrent removal device 33 and the overcurrent removal device 33, and has the load side terminal 25 provided in the base 11. As shown in FIG. When the movable contact 22 contacts the fixed contact 21, the electric circuit between the terminals 24 and 25 turns on, and when the movable contact 22 opens from the fixed contact 21, the terminal ( The electrical circuit between 24 and 25 is turned off.

As shown in FIG. 2, FIG. 3, FIG. 4, the crossbar 30 is arrange | positioned at the bottom part of the base 11, and extends so that it may orthogonally cross the surface of FIG. 2, FIG. 3, FIG. The crossbar 30 is rotated around the shaft center by the opening / closing mechanism part 40, and each movable contact 23 in the circuit interrupting units 20A, 20B, and 20C of each phase is mounted. When the crossbar 30 is rotated about the shaft center, each movable contactor 23 of the circuit breaking units 20A, 20B, and 20C of each phase is rotated at the same time, and by the rotation of the movable contactor 23, The movable contact 22 folds against the fixed contact 21.

In addition to FIG. 2, FIG. 3, and FIG. 4, as shown in FIG. 5, the opening-closing mechanism part 40 is the frame 43 formed from a pair of frame board which mutually opposes, and the pivot axis point in this frame 43. FIG. A substantially U-shaped handle arm 42 (not shown in Fig. 5, shown in Figs. 2, 3 and 4) pivotally supported by P, and fixed to the handle arm 42, It is unitized by the operation handle 41 (not shown in FIG. 5, shown in FIG. 2, 3, 4) operated manually. The inside thereof is engaged with the latch 34 of the overcurrent removing device 33, and is pivoted on the frame bearing portion 43a of the frame 43 by the pivot shaft 44a, and the lever 44 ), An upper link 45 pivotally supported by the link support shaft Q, and a lower link 46 (not shown in FIG. 5) constituting the toggle link by engaging the upper link 45 and the spring pin 47. 2, 3, and 4), and a pair of main springs 48 each having a driven side 48b mounted on a spring pin 47 and a driving side 48a mounted on a handle arm 42, respectively. It consists of.

2, 3, and 4, the upper link 45 is rotatably supported by the link support shaft Q of the lever 44, and the lower link 46 has its lower end. It is connected to the crossbar 30 so that rotation is possible. The operation handle 41 protrudes upward from the cover 12, and is rotated about the rotation axis center point P by manual operation. By the rotation of the operation handle 41, the handle arm 42 is also rotated around the rotation center P together with the operation handle 41. The handle arm 42 becomes an intermediate position in the trip state shown in FIG. 2, becomes a left tilt position in the off state shown in FIG. 3, and becomes a right tilt position in the on state shown in FIG. 4.

As shown to FIG. 6, FIG. 7, the lever 44 is formed from the single metal plate including the lever rotating shaft part 44a, and is arrange | positioned at the inner surface side of each side plate of the handle arm 42. As shown in FIG. The lever pivot shaft portion 44a is formed by bending a portion of the metal plate serving as the lever pivot shaft portion 44a by 90 degrees in the axial direction, and then driving the lever pivot shaft portion to form an arc shaped portion. For example, referring to the cross-sectional shape of the lever pivot shaft portion 44a of the lever 44 shown in FIG. 8, the lever pivot shaft portion 44a has a cross-sectional shape on the one side of the lever 44 as a 'ku' shape. The formed rotational transfer concave portion 44a1 and an arcuate portion 44a2 formed on the opposite side of the rotational transfer concave portion 44a1 are formed in a substantially circular arc-shaped surface whose center angle is greater than 180 degrees. The arc-shaped portion 44a2 is a contact portion in surface contact with the frame bearing portion 43a of the frame 43 in a wide range.

Moreover, as shown in FIG. 9, the lever 44 attaches the projection part 13a of the lever rotation transmission member 13 to the rotation transmission recessed part 44a1 of the lever 44. As shown in FIG. The lever rotation transmission member 13 transmits the rotation of the lever 44 at the time of tripping to an internal accessory device or the like stored in the circuit breaker 100.

In addition, since the axial length of the lever pivot shaft portion 44a is formed by bending the metal plate after bending it, it can be formed larger than the plate thickness of the metal plate forming the lever 44, for example, 3 of the plate thickness. It is possible to provide the rotation shaft part even more than twice the length.

Next, each operation of the circuit breaker 100 on, off and trip will be described.

As shown in FIG. 3, in the off state, the movable contact 22 opens from the fixed contact 21, and these fixed contact 21 and the movable contact 22 are in the open state. In this off state, the handle arm 42 is in the left inclined position and the lower link 46 is in the transverse state. When the operation handle 41 is operated clockwise in the off state shown in FIG. 3, the handle arm 42 rotates clockwise around the rotation center point P together with the operation handle 41, and the handle arm ( 42) rotates to the right inclination position shown in FIG. By the rotation of the handle arm 42, the drive side 48a of the main spring 48 moves clockwise around the pivot center point P of the handle arm 42. By the movement of the drive side 48a of this main spring 48, the load direction of the main spring 48 changes, and the spring pin 47 moves to the right direction from the position shown in FIG. As the spring pin 47 moves, as shown in FIG. 4, the lower link 46 stands in an upright position, the crossbar 30 rotates clockwise, and the movable contact 22 on the movable contact 23. ) Comes into contact with the stationary contact 21.

When the operation handle 41 is operated counterclockwise in the on state shown in FIG. 4, the handle arm 42 rotates counterclockwise around the pivot center P together with the operation handle 41, and the handle arm is rotated. 42 rotates to the left inclination position shown in FIG. By the rotation of the handle arm 42, the drive side 48a of the main spring 48 moves counterclockwise around the rotation center point P of the handle arm 42. As shown in FIG. By the movement of the drive side 48a of the main spring 48, the load direction of the main spring 48 changes, and the spring pin 47 moves to the left direction from the position shown in FIG. By the movement of the spring pin 47, as shown in FIG. 3, the lower link 46 returns to a horizontal state, the crossbar 30 rotates counterclockwise, and the movable contact 23 is movable. The contact 22 is opened from the fixed contact 21 and is turned off.

When the overcurrent removing device 33 operates in the ON state shown in FIG. 4, when the overcurrent removing device 33 pushes the trip bar 35 to rotate, the latch 34 of the trip bar 35 is released. do. As a result, the latch 34 is rotated freely, and the latch 34 and the lever 44 are engaged. Since the lever 44 is always pressed clockwise by the main spring 48, the engagement with the latch 34 is released and rotates clockwise. By the rotation of the lever 44, the handle arm 42 rotates from the right inclination position shown in FIG. 4 to the intermediate position shown in FIG. 2 with the rotation center point P as the center. By the rotation of the handle arm 42, the driving side 48a of the main spring 48 moves relatively to the right side of the spring pin 47, so that an upward force acts on the spring pin 47. do. By the upward movement of the spring pin 47, the crossbar 30 is lifted upward, and the lower link 46 is in an intermediate standing state shown in Fig. 2, and the movable contact on the movable contact 23 is 22 is opened from the fixed contact 21, and will be in the trip state shown in FIG.

Next, the load F2 applied to the lever pivot shaft 44a will be described. As shown in FIG. 10, the load F2 applied to the lever pivot shaft 44a is a reaction force of the force F1 that the upper link 45 pushes up the link supporting shaft Q of the lever 44 to the lever pivot shaft portion 44a. It is added. Here, the force F1 for pushing up the link support shaft Q is pressurized by a pair of main springs 48 mounted on the spring pins 47 that couple the upper link 45 and the lower link 46.

The lever pivot shaft portion 44a also in the on state of FIG. 10A, the off state of FIG. 10B, the trip state of FIG. 10C, and the state during the transition from the on state to the trip state. Perpendicular to the lever pivot shaft portion 44a of the external force applied by the lever pivot shaft portion 44a at a cross section perpendicular to the axis of the lever pivot shaft portion 44a of the lever 44 so as to reduce the contact surface pressure with the frame bearing portion 43a. A component in the in-direction is always configured to apply a load F2 to the arc-shaped portion 44a2 of the lever pivot shaft portion 44a.

As shown in FIG. 11, the engaging part 44b with the latch 34 in the lever 44 is comprised by the curved surface. When the removal device 33 is operated by detecting the overcurrent, the latch 34 is free to rotate, and receives the load from the lever 44 and moves from the 34-1 position of the solid line to the 34-2 position of the double-dashed line. At this time, the load given to the latch 34 by the lever 44 changes from G1 to G2 due to the curved surface formed on the engaging portion 44b. At this time, the distance from the rotation axis center 34a of the latch 34 to the contact point between the lever 44 and the latch 34, which are acting points, changes from the length A before the movement to the length B after the movement. The load G2 after the movement is equal to or slightly larger than the load G1 before the movement, and the distance from the pivot 34a of the latch 34 to the working point is B (after movement) ≥ A (before movement), so that the lever 44 and the latch The rotation moment that the latch 34 receives from the lever 44 increases in the process of releasing engagement with the (34).

According to the present embodiment, the lever 44 is formed of a single metal plate including the lever pivot shaft portion 44a, and has a circular cross-sectional shape having a central angle greater than 180 degrees on the lever pivot shaft portion 44a. By providing the formed arc-shaped portion 44a2, the arc-shaped portion 44a2 is brought into surface contact with the frame bearing portion 43a of the frame 43 in a wide range, whereby the contact surface pressure can be reduced to be low, The durability of the opening and closing mechanism can be improved, and the positional shift can be suppressed.

In addition, since the axial length of the lever pivot shaft portion 44a is formed by bending the metal plate, it is formed to be larger than the plate thickness of the metal plate forming the lever 44, so that the engagement portion with the lever rotation transmission member 13 is formed. We can secure enough.

Further, the direction perpendicular to the lever pivot shaft 44a of the external force applied to the lever pivot shaft 44a in the cross section perpendicular to the axis of the lever pivot shaft 44a of the lever 44 in each of the on, off and trip states. Since the component is always applied to the circular arc 44a2 of the lever pivot shaft 44a, the contact surface pressure of both the lever pivot shaft 44a and the frame bearing portion 43a can be suppressed, thereby repeating the operation. The durability of the opening and closing mechanism of the opening and closing mechanism of the city is improved.

In addition, since the lever pivot shaft portion 44a is formed by bending after a single metal plate is bent, the strength of the shaft portion can be improved, and the positional shift and the accumulation of component dimension errors during joining can be reduced. In addition, component cost and assembly cost can be reduced.

Moreover, the rotation transmission recessed part 44a1 is formed in the lever rotation shaft part 44a of the lever 44, and the projection part 13a of the lever rotation transmission member 13 is formed in this rotation transmission recessed part 44a1. Since it is fitted, the relative rattling in the rotational direction of the lever rotation transmission member 13 and the lever pivot shaft 44a can be efficiently suppressed in a limited space.

In addition, by installing the lever rotation transmission member 13 in the rotation transmission recess 44a1 of the lever 44, rotation of the lever 44 at the time of tripping, etc., is provided in the internal accessory device disposed inside the circuit breaker 100. It can be delivered easily.

Further, by forming a curved surface on the engaging portion 44b with the latch 34 in the lever 44, the removal device 33 is activated by detecting the overcurrent, and the latch 34 is opened in the process of releasing the engagement with the latch. The hanging moment increases the rotation moment applied to the latch 34 without increasing the load applied to the removal device 33, so that the tripping operation can be stabilized and the reliability of the circuit breaker can be improved.

In addition, in this embodiment, although the example of the 1-point breaker type circuit breaker which has a movable contact in the one end of a movable contactor was demonstrated, the two-point breaker type circuit breaker which has a movable contact in both ends of a movable contactor is a switch in this embodiment. Needless to say, it is possible to apply the bend, and the same effects as in the present embodiment are obtained.

Embodiment 2 Fig.

12 is a side view illustrating the lever pivot shaft 44a according to the second embodiment.

In this embodiment, the arc-shaped portion 44a2 of the lever pivot shaft portion 44a is formed in an arc portion 44a3 having a central angle of about 180 degrees and an extension portion on the circumscribed circle of the arc portion, as shown in FIG. The contact part 44a4 which contacts the frame bearing part 43a of the frame 43 is comprised. The center angle of the arc-shaped portion 44a2 is larger than 180 degrees in the range of adding the arc portion 44a3 to the contact portion 44a4. Since it is the same as that of Embodiment 1 about another structure, description is abbreviate | omitted.

In the first embodiment, the forming process such as cutting or cutting is performed on the cross-sectional arc which is the cutting surface of the single metal plate forming the lever 44. However, in the present embodiment, the cross section of the lever 44 is used as it is. The contact portion 44a4 is in contact with the frame bearing portion 43a of the frame 43. The distal end of the contact portion 44a4 is more preferably not in point contact with the frame bearing portion 43a by, for example, chamfering or cutting.

According to the present embodiment, the lever 44 is formed of a single metal plate including the lever pivot shaft portion 44a, and has a circular cross-sectional shape having a central angle greater than 180 degrees on the lever pivot shaft portion 44a. By providing the formed arc-shaped portion 44a2, the arc-shaped portion 44a2 comes into contact with the frame bearing portion 43a of the frame 43 in a wide range, whereby the contact surface pressure can be suppressed low, and the opening and closing mechanism portion at the time of repeated operation The durability can be improved and the positional shift can be suppressed.

In addition, by simplifying the processing of the cross section of the single metal plate forming the lever 44, a part of the process of providing the lever pivot shaft 44a can be reduced, and the cost can be reduced.

Although the circuit breaker has been described in the above description, it is natural to be able to use the overall switch of this kind, and even minute changes are not intended to depart from the scope of the invention.

21 fixed contacts, 22 movable contacts,
23 movable contactors, 30 crossbars,
33 remover, 34 latches,
42 handle arms, 43 frames,
44 lever, 44a lever pivot,
44a2 arc, 47 spring pins,
48 main spring, 45 upper link,
46 lower link, 100 circuit breaker.

Claims (8)

A movable contact having a movable contact at one end or both ends thereof, a fixed contact folded with the movable contact, a crossbar holding the movable contact and pivotally supported, and a crossbar A lower link for driving the lever, a lever engaged with a latch of the removal device and pivoted by a bearing part of the frame during tripping, and a pivot pin supported by the lever and a spring pin on the lower link. An upper link coupled to the upper link to form a toggle link together with the lower link, a main spring coupled to the spring pin, and a driving side of the main spring coupled to a case of the circuit breaker. A handle arm pivotably pivoted to a fixed frame,
And the lever is formed of a single metal plate including the rotation shaft portion of the lever, and the rotation shaft portion has an arc shape portion formed with a surface having a cross-sectional shape having an arc shape with a central angle greater than 180 degrees. The method according to claim 1,
And the lever is provided on a rotation shaft of the lever, and has a rotation transmission recess for transmitting the rotation of the lever. The method according to claim 2,
And a lever rotation transmission member fixed to a rotation shaft of the lever, the lever rotation transmission member having a projection fitted to the rotation transmission recess. The method according to claim 1 or 2,
A circuit breaker, characterized in that the cross-sectional shape of the arc-shaped portion provided in the rotating shaft portion of the lever is an arc. The method according to claim 1 or 2,
The arc-shaped part provided in the rotational shaft part of the said lever has a circular arc part which forms a part of the said arc-shaped part, and is provided in the extension part on the circumscribed circle of this arc part, and the contact part which contacts the bearing part of the said frame, The circuit breaker characterized by the above-mentioned. . The method according to claim 1 or 2,
And the pivot shaft portion of the lever has an axial length larger than the plate thickness of the lever. The method according to claim 1 or 2,
And a component in a direction perpendicular to the axis of the external force applied to the lever shaft in a cross section perpendicular to the axis of the pivot shaft portion of the lever to always face an arc shaped portion provided on the pivot shaft portion of the lever. The method according to claim 1 or 2,
The engaging surface of the lever with the latch is formed in a curved shape, circuit breaker, characterized in that to increase the rotation moment received by the latch from the lever in the process of the engagement with the latch.

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